Ventilating apparatus



- Oct. 25, 1938. A. G. OREAR VENTILATING APPARATUS Filed Feb. 10, 1936 3 Sheets-Sheet 1 www/ QQQUmEQU @UUBUUUQ BUUQUUEUQ UUESQQUQ JQU@@B a? @Qwmm a? mfiwmma m mmmm mim mfimmmmUU M g 5 as Oct. 25, 1938. A. c5. OREAR I 2,134,142

VENTILATING APPARATUS Filed Feb. 10, 1936 3 Sheets-Sheet 3 j/w en fo Patented Oct. 25, 1938 UNITED STATES PATENT oFiucE VENTILATDNG APPARATUS Andrew G. Orear, Glendale, CaliL, assignor to Trade-Wind Motortans, Inc., Los Angeles,

CaliL, a corporation 01 California Application Februarylo, 1936, Serial No. 63,196

Claims. (01. sis-'43) dence kitchens and for small commercial applications having relatively small air volume.-

When this type of fan is used at quiet operating speeds with ducts of appreciable length or having turns or elbows its capacity is decreased rapidly and tends to overload the driving motor. Further, the motor of a typical propeller type fan is in the air stream and subjected to the heat, dust, grease,- etc. passing over the same. A blower type fan or centrifugal type fan as heretofore provided and manufactured requires a large space for housing it, and requires the dampening of vibration by providing special mountings for the motor and fan and noise and vibration dampening and absorbing connections with the air ducts, etc. Where the use of ducts to convey. the air to or from definite spaces is desirable centrifugal or blower type fans are required to build up suflicient pressure to overcome the friction to air flow in the ducts or duct systems. The inconvenience and added cost of providing the required space for a blower type fan or centrifugal fan, the special mountings and the duct connections necessary for the quiet operation of a typical blower type fan have made it impractical to employ the necessary or required fans in such situations.

Another object of this invention is to provide ventilating unit embodying a blower type fan which unit may be mounted in 'a verylimited 40 space, for example, in a typical wall or ceiling structure, and does not necessitate special costly mountings or special flexible connections and fittings to the air ducts.

Another object of this invention is to provide a ventilator or ventilating apparatus of the character'mentioned in,which the noise and vibration generated by the motor and fan wheel or rotor are fully dampened and absorbed immediately adjacent the points where they are generamd.

Another object of this invention is to'provide a blower type fan ventilating unit of the character mentioned in which the casing that houses the motor and fan rotor unit and provides the fan chamber, the air inlet and the air outlet, is a compact unit that may be permanently or rigidly installed and may have direct metal connection with the air duct.

Another object 01 this invention is to provide a motor driven ,ventilator or ventilating unit that may be mounted in a wall or ceiling structure to be entirely enclosed within such structure.

Another object of this invention is to provide a motor driven ventilator of the character mentioned in which the motor and the blower or fan rotor may be very easily removed for inspection, cleaning, servicing, etc. without disturbing the casing, the wiring, the air duct, or any parts of the ceiling or wall structure.

Another object of this invention is to provide a motor driven ventilator of the character mentioned in which the driving motor and the blower or 'fan rotor constitutes a single unit removably held in the casing by a simple, novel means to be easily and conveniently removed through the outer or inlet end of the casing.

Another object of this invention is to provide a motor driven ventilator of the character mentioned that embodies a compact housing structure or casing enclosing the various other parts and formed and proportioned for arrangement in a typical wall structure, for example, a ceiling structure, and between its joists or studs.

Another object of thisinvention is to provide a. motor driven ventilator or ventilating apparatus operable to develop sufiicient static pressure to overcome the resistance to air flow encountered in ducts or duct systems, and that is particularly smooth running and quiet making a minimum of sound or noise and not subject to vibration when in operation. 7

Another object of this invention is to provide animproved ventilator of the character mentioned in which the motor is not in the main air stream of the blower but is cooled by a forced or positive draft of air induced into the main air stream of the fan or blower rotor through slots of spaces. in the motor mounting.

The various objects and features of my invention will be fully understood from the following detailed description of typical preferred, forms and applications of my invention, throughout which description reference is made to the accompanying drawings, in which:

' Fig. l is a side elevation of one form or embodiment of the invention showing it mounted in a typical building or ceiling structure. Fig. 2 is a bottom view of the apparatus shown in Fig. 1. Fig.3 is a longitudinal or vertical detailed sectional view of the apparatus illustrated in Fig. 1.

Fig. 4 is a transverse detailed sectional view taken substantially as indicated by line 4-4 on Fig. 3 with a portion of the rotor in section. Fig. 5 is an enlarged fragmentary detailed sectional view of the vibration absorbing mounting of the motor and rotor unit. Fig. 6 is a vertical detailed sectional view of another form or embodiment of the invention illustrating it mounted in a wall or ceiling structure and Fig. 7 is a view taken substantially as indicated by line 1-1 on Fig. 6 illustrating certain parts in transverse cross section.

In thedrawings I have illustrated typical embodiments of the invention mounted in a typical wall or ceiling structure. It is to be understood that the invention is adapted to be embodied in forms for use in various situations and for usein various types of wall, ceiling and building structures. Accordingly, the invention is not to be considered as limited or restricted to the specific forms or applications of the invention illustrated in the drawings but is to be taken as including anyfeatures or modifications that may fall within the scope of the claims.

The particular wall or ceiling structure illustrated in Figs. 1 to 5 of the drawings comprises the usual horizontally spaced wooden joists III which support a sub-floor II and a finished floor I2.- Lath I3 is secured to the lower sides of the joists l8 and plaster |4 covers the laths. The apparatus or ventilating unit of the present invention is adapted to be arranged in the wall or ceiling structure between two spaced poists l3 and between the sub-floor H and the lath and plaster i3 and I4. An opening I5 is provided in the lath and plaster l3 and H between the joists Hi to receive the unit. In the particular case illustrated the opening I! is substantially equally spaced between two joists I0, it being understood that the opening may be otherwise disposed, if desired. In the particular application of the invention about to be described it is preferred to provide a wooden frame it in the opening I! to facilitate the mounting of the ventilator, it being understood that the frame I6 is not essential in all installations. The frame i3 may be built in the wall or ceiling structure at the time of its erection but is not necessary where the ventilator is to be employed in a previously constructed wall or ceiling. The frame It is rectangular and, if desired, may be attached to or connected with the joists l0.

The embodiment of the present invention illustrated in Figs. 1 to 5 of the drawings includes, generally, a housing or casing supported by the frame l3 to be within the space defined by the spaced joists It, the sub-floor II and the lath 3. a motor and fan rotor unit l3, and a vibration absorbing means i3 for mounting the unit l8 in the casing |'I.

The casing I1 is provided to house the motor and fan rotor unit l3, to provide the blower or fan chamber, and the inlet and outlet for the fan chamber. The casing I! is preferably sectional comprising a principal section or main section 20, an end plate 2| for the section 23 and an upper section 22. In accordance with the broader aspects of the invention the sections 23 and 22 and the plate 2| may be formed of any suitable material. In practice it has been found desirable to make the section 20 and the plate 2| in the form of castings of aluminum or the like and to form the section 22 of sheet metal. The main section 23 is cylindrical in its general external configuration. The casing section 20 i5 tubular or hollow having the blower chamber or fan chamber 23. The side wall of the chamber 23 is substantially vertical and is volutely curved or in the nature of a scroll wall to promote the efllciency of the fan or blower as is well understood by those skilled in the art. The chamber 23 has an opening 24 in its volute side wall between its portions of the largest and smallest radii. The opening 24 is the outlet to discharge the air handled by the fan or blower. A flange 25 may be provided on the section 23 around the outer end of the outlet opening 24 and the wall of the opening 24 and the flange 25 are extended upwardly and outwardly at the upper end of the opening 24 as shown in the drawings. An air duct or discharge conduit 26 is secured to the flange 25 to receive the air from the outlet opening 24. In accordance with the invention this duct 23 may be of metal or any other desired material and may be directly secured to the flange 25 as by bolts or screws 21. The duct 2.3 may extend to discharge at any desired point.

The lower end of the casing section 23 is provided with an internal recess 28 and an external flange 29. In the particular case illustrated in the drawings the recess 28 and the flange 23 are polygonal or octagonal it being understood that they may be of any desired shape. The recess 23 is open to or in communication with the outlet opening 24 and the fan opening or chamber 23. An adapter 30 is shown mounting or securing the casing section 20 to the frame I3, it being understood that the adapter 38 may be varied to suit various conditions and in some cases may be eliminated. The lower end of the flange 23 may directly bear on the adapter 38' and the section 23 may be secured to the adapter 30 by screws 3|. In the structure illustrated in the drawings the adapter 30 has upwardly projecting wings 32 and screws 33 pass through openings in these wings 32 and thread into openings in the flange 28 to further secure the section 20 to the adapter. The adapter 38 fits in the frame it and has cutwardly projecting horizontal flanges 34 at its lower end secured to the frame It by screws 35, or the like. The adapter 30 serves to mount or support the section 23 of the casing l1 directly on the frame It of the wall or ceiling structure.

The principal or main casing section 20 may be provided with an integral wiring box or pull box 33 to receive the leads 3'! to the fan operating motor, the power supply conductors 38, the splices between the leads 31 and the supply lines 33 and any other required electrical fittings. In the form of the invention illustrated the box 33 projects from the side of the section 28 adjacent the outlet flange 24. Openings 33 are provided in the walls of the box 36 to receive the supply lines 33 and their conduit or conduits 48. The interior of the box 36 is accessible through an opening 4| in its lower end which communicates with the recess 28. An opening 42 may be provided in the outer side of the box 36 and may be normally closed by a removable cover plate 43.

The end plate 2| partially closes the lower end of the fan chamber 23 and has an opening 44 forming the inlet for the fan chamber 23. The plate 2| is removably received in the recess 23, the recess being proportioned to fully or entirely receive the plate. The plate 2| conforms, generally, to the configuration of the recess 23 and is secured to the section 20 by suitable screws 48 threaded into openings in the lower end of the section. The end plate 2| is provided with a web 41 closing the lower opening 4| in the pull box 7 36. In the preferred construction illustrated in the drawings the plate 2| closes the lower side of the outlet 24. A tongue 46 projects outwardly from the plate 2| and closes or forms the wall of the lower end of the outlet 24. The tongue 43 fits over the adapter 30 and is 'curved upwardly and outwardly to facilitate the easy positioning and removal of the end plate 2|. The upper surface of the plate 2| is provided with a recess 49 whose outer wall conforms to the outer wall of the 'volute fan chamber 23. The recess 49 may extend inwardly to adjacent the inlet opening 44 and' is. provided to receive any foreign matter, grease or oil that may fall from the fan rotor. Further. the recess 49 may be shaped so that the plate 2| offers a minimum resistance to air flow in the fan chamber 23. The upper side of the tongue 49 may have I an inclined surface 56 sloping upwardly and outwardly from the recess 49 to the duct 26.

The upper section 22 of the casing I1 is arranged on the upper end of the main section 26 to enclose the driving motor of the unit I9. The section 22 is a cup-like part having a substantially cylindrical side wall and a substantially fiat horizontal upper wall. The upper end portion of the main section 26 is cylindrical and reduced in diameter and the lower end portion of the upper section 22 engages or telescopes over this cylindrical part 5|. Suitable screws 52 may removably secure the section 22 to the reduced part 5| of the section 20. A vertical opening 53 extends through the reduced part 5| .and communicates with the fan chamber or blower chamber 23 and the interior of the casing section 22. The opening 53 and the interior or opening of the section 22 are concentric or aligned with the inlet opening 44. It is preferred to provide a plurality of spaced openings 54 in the upper portion of the casing section 22 to provide for the cooling or ventilating of the motor as will be hereinafter described.

The motor and fan wheel or rotor unit I8 is removably mounted in the casing IT by the vibration absorbing mounting means 19. The removable unit It includes a driving or operating motor 55 and a fan wheel or fan rotor 56. The motor 55 may be an electric motor of the desired or necessary rating, etc. The motor 55 includes a typical case comprising two bell-like sections 57. The motor 55 is arranged longitudinally in the upper casing section 22 and has suitable clearance with its internal walls.

The fan wheel or rotor 56 is preferably of the centrifugal type and may include a flanged hub 58. fixed to the motor shaft 59 by a set screw60. The blower or fan rotor 56 has impellers or impeller blades 63 extending between a plate 6|- and a ring 62. The blades 63 are transversely curved to be effective in throwing or tangentially discharging the air outwardly from the periphery of the rotor 56. The opening of the rotor ring 62 may be slightly'smaller in diameter than the inlet opening 44.

The unit I8 is mounted in the casing I! by the means l9 so that the axis of rotation of'the motor shaft 59 and the rotor 56 is substantially concentric with the axis of the inlet opening 44 and so that the periphery of the rotor 56 is relatively close to the side wall of the fan chamber 23 adjacent a side of the outlet opening 24 and the chamber space between the rotor 56 and the wall of the chamber 23 increases circumferentially to a maximum at the outlet opening 24. This positioning of the rotor 56 in'the chamber 23 provides for the most efficient handling of the air by the rotor and for the mosteflicient compression and flow of air for passage through the outlet 24 and the duct 26. It will be noted that the blower proper or fan proper comprises or is made up of the casing section 20 having the fan chamber 23 and the motor driven fan wheel or rotor in the chamber 23; the casing section 26 being permanently or rigidly mounted, as above described.

The .means l9 for mounting the motor and fan rotor unit I8 is an important feature of the in-' vention as it supports the unit l8 in a manner that permits the casing I! to be permanently or at least rigidly mounted, the means l9 acting to absorb all vibration produced by the motor 55 and .the rotor 56 so that no vibration is transmitted to the casing I1 or any parts associated with the casing. The only sounds or noises pro-'- duced by the apparatus are the magnetic or electrical sounds in the motor 55 and the sound produced by the action of the rotor 56 on the air and these sounds and all other mechanical as well as electrical vibrations are absorbed and dampened by the mounting means l9 and are not transmitted to the casing H. The mounting means I9 supports the unit I6 so that it may be readily removed bodily from the casing.

The improved mounting means l9 includes an upper or inner member 64 and a lower or outer member 65, both of which are secured to the lower or outer end of the motor 55. In practice the members 64 and 65 are annular or in the form of rings. The member 64 is shaped to receive. the lower end portion of the lower or outer motor casing section 51 having an annular socket or recess 66 whose wall conforms to and properly cooperates with the motor casing section. The member 64 has a fiat face 61 on its lower or outer side which is preferably substantially normal to the axis of rotation of the motor shaft 59. A complementary or abutting face 68 is provided on the upper or inner face of the member 65. A downwardly and outwardly inclined surface 69 is provided on the member 64 and extends inwardly from its periphery. The member 65 has a surface spaced from and substantially parallel with the'surface 69. The mounting members 64 and 65 may be directly secured together by screws 9. In the structure illustrated in the drawings screws H extend longitudinally through the outer portion of the motor case sections 51, pass through openings in the member 64 and thread into openings 12 in the member 65 to aid in securing the members to the motor. It will be seen that the screws 9 and H serve to secure the motor casing sections 51 on the motor 55 and clamp the members 64 and 65-together on the lower or outer end of the motor casing. The members 64 and 65 just described form an element directly engaging and directly secured to the motor 55 and having or providing a space 13 whose walls are inclined with respect to the axis of rotation of the motor shaft 59.

The mounting means l9 includes a ring or member 14 removably secured to the casing H. In the construction illustrated in the drawings the mounting member 14 is secured tothe casing section 20 at the upper wall of the fan chamber 23. The means for removably securing the mounting member 14 to the section comprises spaced parts projecting from the wall 15, which parts may be in the form of screws 16 having heads 11 at their outer or lower ends.

Lugs 18 are provided on the periphery of the member 14 and each lug has a slot 19 to receive thescrews member 14 or the unit I8 is positioned where the screws 18 occupy the inner ends of the slots 18 the screws may be tightened or threaded inwardly so that their heads 11 cooperate with the depressions 88 'to dependably lock the member 14 and the unit l8 associated therewith to the casing l1.

The mounting member 18 is provided with an inwardly projecting lip 8|. The lip 8| is preferably annular and is provided withilat substantially parallel sides. The lip 8| projects into the space 13 between the members 88 and 88 and is inclined so that its surfaces are substantially parallel with the surfaces 88 and 10. The mounting means i8 includes sections or blocks 82 of vibration absorbing material interposed between the surfaces 89 and 18 and the opposing side surfaces of the lip 8|. The blocks 82 may be formed of rubber, rubber composition or other material effective in absorbing and dampening vibration. The blocks 82 are preferably spaced apart circumferentially of the assembly of members 84,88 and 14 and are elongate parts wrapped or turned over the inner circumference of the lip 8| to each have substantially" equal portions held or interposed between the lip 8| and the surface 89 and the lip 8| and the surface 18. The blocks 82 of vibration insulating material are held in position by being clamped between the surfaces 88 and 18 and the lip 8L. It will be seen that tightening of the screws 8 and 1| serves to clamp or hold the blocks 82 compressed between the surfaces 88 and 18 and the lip 8|. An upwardly or inwardly projecting annular ridge 83 may be provided on the upper or inner side of the member 14 to positively hold the upper'arms or parts of the blocks 82 against outward displacement. It is to be particularly noted that the blocks 82 held between the surfaces 88 and 18 and the lip 8| are inclined relative to the axis of rotation of the motor 88 so that the weight of the unit I8 and vibratory motion resulting from operation of the unit l8 act in lines substantially diagonally of the greatest cross sectional dimensions of the blocks.

The blocks 82 of vibration absorbing material support the unit I8 for what may be termed full floating motion, that is, the unit l8 may move a limited extent in any direction relative to the fixed or stationary casing l1. The blocks l8 serve as the sole means for supporting the unit i8 on the casing l1 through the medium of the lip Bi and, therefore, fully absorb all vibration resulting from the operation of the motor 88 and the fan rotor 88 so that no vibration is transmitted to the casing H or parts associated therewith. In accordance with the invention the spaces between the spaced blocks 82, that is, the

portions of the space 18 not occupied by the blocks 82 form air passages connecting the interior of the section 22 with the fan chamber 28. The main stream of air from the fan rotor 88 flowing out through the outlet 28 creates a reduced pressure in the upper portion of the chamber 23 and thus inducesor draws air inwardly through the space 18. This produces a positive flow of cooling and ventilating air through the casing section 22 to cool and ventilate the motor 85. The air enters the casing section 22 through the openings 88, passes through the chamber of the section 22 and flows through the space 18 into the main stream of air from the rotor 88.

To permit the ready removal of the motor and fan rotor unit I8 from the casing |1 without disturbing the electrical wiring, a releasable connection 88 is provided in the motor'leads 81 at a point between the motor 88 and the box 88. This connection 88 may be in the form of a suitable plug and socket connection capable of being broken or released by pulling apart or unthreading its sections. A suitable grill 88 may be provided over the inlet opening of the adapter 88. The grill 88 obviously may be of any design and character. In the simple form illustratedthe grill 88 is a flat grill having a plurality of rectangular openings 81. The grill 88 may be held in position by screws 88 threaded into the frame i8. It is to be understood that the motor 88 of the unit I 8 may be controlled by a suitable switch (not shown) at any desired and convenient remote point.

It is believed that the operation of the ventilating apparatus illustrated in Figs. 1 to of the drawings will be readily apparent from the foregoing detailed description. Assuming that the apparatus is mounted or arranged as illustrated and described, its motor 88 maybe energized as desired by the closing of a remote convenient switch. During operation of the motor 88 the rotor 88 rotates at a suitable speed in the chamber 28 and its blades 88 operate through a centrifugal action to throw air from the periphery of the rotor thus creating a reduced pressure in the interior of the rotor. A reduced pressure in the rotor of course induces an air flow upwardly through the grill 88 into the intake opening 88 into the rotor. The air thrown or discharged from the centrifugal rotor 88 is compressed and caused to flow outwardly through the chamber 28 through the outlet 28 into the duct 28 and is driven or forced therethrough by the action of' the'rotor. As previously described the apparatus operates with little or no vibration. The mounting means l8 operates toabsorb all vibration produced by operation of the motor 88 and the rotor 88 so that such vibration is not transmitted to the casing |1. Accordingly, the casing |1 not being vibrated may be directly connected withthe air duct 28 and the supports and mountings without causing the production of vibration and sound in these parts. The recess 48 in the upper side of the end plate 2| dependably traps any grease, foreign matter or oil that may fall from the rotor 88, preventing the passage of such matter into the room.

When it becomes necessary or desirable to service the motor 88 or to clean or service the rotor 88 the unit |8 may be easily bodily removed from the casing I11 To remove the unit l8, the grill 88 and the end plate 2| are first removed. These parts may be easily removed by unthreading their securing screws or bolts. Following the removal of the grill 88 and the end plate 2| the screws 18 may be threaded downwardly or loosened to some extent to disengage their heads 11 from the depressions 88. Following this loosening of the screws 18 the unit l8 may be turned slightly to disengage the slots 18 from the screws 18. The unit 18 may then be moved downwardly or outwardly through the casing i1. It is, of course, desirable to break or disconnect theconmotion 88 so that the wiring of the motor does not have to be disturbed. In practice the leads or wires 31 extending to the motor 88 may be of suflicient length to permit the ready disconnection of the connection 66. It is to be noted that the removal of the unit I6 from the casing I! does not necessitate disturbing or loosening the vibration absorbing elements of the mounting means I9. Further, it will be noted that the wiring in the box 66 may be easily inspected and made accessible by merely removing the grill 66 and the end plate 2I. The unit I6 is such that it may be easily cleaned and serviced when removed from the casing I I and the unit may be easily and quickly remounted in the casing IT. The unit I6 may be replaced and secured in the casing I I as described above by manipulating it so that the inner ends of the bayonet slots I8 receive the screws 16 whereupon the screws 16 may be tightened to bring their heads 11 into the depressions 80. The connection 85 is, of course, preferably made up or connected before the flnal securing of the unit I6 in the casing.

The apparatus illustrated in Figs. 1 to 5 of the drawings may be mounted in various manners and positions other than those shown in the drawings. In certain installations it may be desirable or necessary to support the apparatus by means of hangers secured at their ends to supports such as parts of a wall or building structure, and secured between their ends to the casing section 20 by screws or the like threaded in openings in shoulders 68 on the section. The flange 29 at the inlet of the casing is particularly adapted to form a mounting or attaching means for the apparatus. The flange 29, if desired, may form the sole or principal mounting attachment for the apparatus and may be directly secured to a wall or building structure, to the duct at the discharge or inlet end of a ventilating or air conditioning system, etc. The flange 25 at the discharge of the casing may also serve as a mountingfif desired. It is to be noted that the mounting means I9 for the unit I6 is such that the apparatus may be mounted with the unit I8 in a vertical position, an inclined position, or a horizontal position without modification of any parts of the apparatus proper.

Figs. 6 and '7 of the drawings illustrate a form of the invention embodying a lamp or lighting unit. The casing H, the motor and fan rotor unit I8 and the mounting means I6 of the apparatus shown in Figs. 6 and 7 may beth'e same as described above and corresponding reference I numerals are employed throughout the drawings for these elements and their several parts. The form of the invention illustrated in Figs. 6 and '7 may be supported by hangers 90 secured at their ends to the joists I0 or other parts of the building structure and secured intermediate their ends to the shoulders iii? of the casing section 20 by screws or bolts. When the unit or device is sup ported in this manner the above described adapter 30 may be dispensed with, if desired.

The form of the invention being described includes a grill SI for the air inlet 01. the apparatus that preferably, though not necessarily, projects downwardly or outwardly beyond the surface of the ceiling or wall, as shown in the drawings. The grill Si is ornamental in design or configuration and is provided with spaced air inlet openurge-92. A fiange 93 isprovided on the upper end of the grill 9! and may be flush with or may bear against the plaster I4 and is secured to the flange 29 of casing section 20 by screws 94 or the like. The grill 9| thus supported is readily removable to permit the removal of the'unit I8 and to provide for easy access to the interior of the apparatus. The grill 9i has a central opening or to carry a suitable globe 66 for the lamp 61. An

electric socket I00 is secured to the upper side of the web 41 to project into the box 36. A lead or wire extends from the socket I00 to a suitable remote switch and the other lead from the socket I00 may be connected with a supply line 36. Conductors IIII are provided for the lamp socket 96 and may carry a plug I02. The plug I02 is adapted to be plugged in or pressed in the socket I00 to connect the lamp socket 66 with its supply conductors. It will be apparent that the lamp 91 may be controlled from a conveniently located remote switch.

The apparatus illustrated in Figs. 6 and 7 operates in the same manner as the previously described form of the invention. This embodiment of the invention embodies the conveniently and attractively located lamp 91. The grill 6i carrying the lamp 61 and its associated parts may be easily and quickly removed by removing the screws 64 and by pulling the plug I02 from the box or socket I00. Following removal of the grill 6| the end plate 2| may be removed to render the wiring in the box 36 accessible and to permit the easy removal of the unit I6 from the casing I in the manner above described.

Having described only typical preferred forms and applications of. my invention, I do not wish to be limited or restricted to the specific details herein set forth, but, wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims: Y

Having described my invention, I claim:

l. A ventilating means for installation in a building wall having an opening, the means comprising a casing having a chamber with a volutely curved side wall, the chamber having an open lower end forming an air inlet and having a the casing in said opening in the building wall to be entirely within the same and above the plane of the external surface of the'wall, and a unit insertable in and removable through the lower end of the chamber, the unit including a centrifugal type blower wheel rotatablevin the chamber'and related to its volutely curved wall to force air out through the outlet, and a motor above the blower wheel for driving the same, said unit being entirely above the plane of the external surface of the wall.

2. A ventilating means for installation in a building wall having anopening, the means comprising a casing having a chamber with a volutely curved side wall, the chamber having an open end forming an air inlet and having a lateral air outlet, means for supporting-the casing to be entirely within the said opening where the said air inlet is open at an external face of the building wall, a unit for arrangement in the casing including a centrifugal type blower wheel, and a motor for driving the wheel, the unit being insertable in and removable through the open end of. the chamber, and means removably supporting the unit in the casing to have all of its parts inward of the external surface of the building wall and so that the wheel is in the chamber and is related to its volutely curved wall to force air out through the outlet and the motor is inwardly of the chamber with respect to said external wall.

3. A ventilating means for installation in an opening in a building wall, said means including, a casing having an inner chamber and an outer chamber, the outer chamber having a volutely curved wall, an open outer end and an air outlet in said volutely curved wall, means for supporting the casing in said opening to be entirely within the same with the open end of the outer chamber open to the atmosphere at the external surface of the building wall, a unit adapted to be inserted in and removed through said open end of the outer chamber and including a motor, and a centrifugal type blower wheel driven by the motor, and means for removably securing the unit in the casing to be entirely housed therein so that the motor and blower wheel are both entirely within the building wall with the motor in the inner chamber and-the blower wheel in the outer chamber where it is related to the volutely curved wall to draw air through said open end of the outer chamber and expel it through the outlet.

4. A ventilating means for installation in an opening in a building wall, said means including, a casing having an inner chamber and an outer chamber, the outer chamber having a volutely curved wall, an open outer end and an air outlet in said volutely curved wall, means for supporting the casing in said opening to be entirely within the same with the open end of the outer chamber open to the atmosphere at the external surface of the building wall, a unit adapted to be inserted in and removed through said open end of the outer chamber and including a motor, and a centrifugal type blower wheel driven by the motor, and means for removably securing the unit in the casing to be entirely housed therein so that the motor and blower wheel are both entirely within the building wall with the motor in the inner chamber and the blower wheel in the outer chamber where it is related to the volutely'curved wall to draw air through said open end of the outer chamber and expel it through the outlet, the last mentioned means including parts partitioning the inner chamber from the outer chamber.

5. A ventilating means for installation in an opening in a building wall, said means including, a casing having an inner chamber and an outer chamber, the outer chamber having a volutely curved wall, an open outer end and an air outlet in said volutely curved wall, means for supporting the casing in said opening to be entirely within the opening with the open end of the outer chamber open to the atmosphere at the external surface of the building wall, a unit adapted to be inserted in and removed through said open end of the outer chamber and including a motor, and a centrifugal type blower wheel driven by the motor, and means for removably securing the unit in the casing to be entirely housed therein so that'both theblower wheel and motor are inward-from said external surface of the wall with the motor in the inner chamber and the blower wheel in the outer chamber where it is related to the volutely curved wall to'draw air through said open end of the outer chamber and expel it through the outlet, the last mentioned means partitioning the inner chamber from the outer chamber whereby the motor is out of the air stream of the wheel, the. said last mentioned means having air ducts connecting the chambers whereby the air stream oi the wheel induces an air current in the inner chamber to cool the motor.

6. A ventilating means for installation in an opening in a building wall, said means including, a casing having aninner chamber and an outer chamber, the outer chamber having a volutely curved wall, an open outer end and an air outlet in said volutely curved wall, means for supporting the casing in said opening to be entirely within the same with the open end of the outer chamber open to the atmosphere at the external surface of the building wall, a unit adapted to be inserted in and removed through said open end of the outer chamber and including a motor, and a centrifugal type blower wheel driven by the motor, means for removably securing the said unit in the casing to be" entirely housed therein so that both the blower wheel and motor are inward from said external surface of the wall with the motor in the inner chamber and the blower wheel in the outer chamber and operatively related to said volutely curved wall to force air out through the outlet, and an annular plate secured to the casing at the open outer end of the outer chamber to define the air inlet, the plate having a trap groove facing inwardly with respect to the outer chamber.

7. Ventilating apparatus for installation in a building wall having an opening, the apparatus including, a casing adapted to be inserted through the opening, an adapter to be secured in the opening to support the casing where it is entirely within said opening, the casing having a blower chamber with a volutely curved side wall, an open end forming an air inlet to communicate with the atmosphere at the external surface of the wall and a lateral air outlet, a unit adapted to be passed through said open end of the chamber when the casing is supported in the adapter, the unit comprising a centrifugal blower wheel, and a motor for driving the wheel, and means accessible through said open end of the chamber removably supporting the unitin the casing for removal through the said open end of the chamber for servicing and normally supporting the unit where the wheel is within said chamber in operative relation to the volutely curved wall to force air out through the outlet and the motor is inward of the chamber with respect to its open outer end so that the entire unit is within the building wall.

8. Ventilating apparatus for installation in a building structure ceiling having an opening, the apparatus including, a casing adapted to be inserted through the opening, a flange on the easing fitting the opening to support the casing where it is entirely above the lower surface of the ceiling, the casing having a blower chamber with a volutely curved wall, an open outer end and an air outlet, a blower unit insertable through said open end of the'casing, the unit comprising a motor and a centrifugal blower wheel driven by the motor, and means for removably supporting the said unit in the housing to be entirely the said lower surface of the ceiling and where the wheel is in said chamber in operative relation to its volutely curved wall to draw air through the open end of the chamber and force 4 it out through the outlet.

ANDREW G. OREAR. 

